Method for purifying a fermentation-derived product

Abstract

Process for purifying a fermentation-derived product.

1 . A process for purifying a cell-derived product from a cell culture, said process comprising treating an extract of the cell culture or a growth medium of the culture at a temperature between about 60° C. to 90° C. and cooling the treated extract or growth medium to a temperature below about 60° C.  
     
     
         2 . A process according to  claim 1 , further comprising subjecting the treated extract or growth medium to a separation step that separates the extract or growth medium into a precipitate and a soluble portion.  
     
     
         3 . A process according to  claim 1 , wherein the treatment at a temperature between about 60° C. to 90° C. is for a period of time between about 1 min and about 60 min.  
     
     
         4 . A process according to  claim 3 , wherein said time period of between about 1 min and about 30 min.  
     
     
         5 . A process according to  claim 4 , wherein said time period is not more than about 10 min.  
     
     
         6 . A process according to  claim 1 , wherein the extract or growth medium is cooled to a temperature below about 35° C.  
     
     
         7 . A process according to  claim 1 , wherein the cell culture is selected from the group consisting of bacterial and yeast cells.  
     
     
         8 . A process according to  claim 8 , wherein the cell culture is selected from the group consisting of  Escherichia coli, Saccharomyces cerevisiae, Pichia pastoris, Pichia methanolica, Candida utilis  and  Kluyveromyces lactis.    
     
     
         9 . A process according to  claim 1 , wherein the cell culture comprises recombinant cells.  
     
     
         10 . A process according to  claim 1 , wherein the cell-derived product is a protein.  
     
     
         11 . A process according to  claim 10 , wherein the protein has a molecular weight below about 25,000 daltons.  
     
     
         12 . A process for purifying a fermentation-derived product, said process comprising the steps of: 
 a) heating the fermentation broth containing said fermentation-derived product or a precursor thereof to a temperature in the range from 60° C. to 90° C.,    b) cooling the fermentation broth to a temperature below 60° C.;    c) separating the precipitate from the soluble portion of the fermentation broth at a temperature less than 60° C.; and    d) isolating said fermentation-derived product.    
     
     
         13 . The process according to  claim 12 , wherein no flocculation agent is added to said fermentation broth.  
     
     
         14 . The process according to  claim 12 , wherein the temperature of the fermentation broth during the separation step c) is less than about 40° C.  
     
     
         15 . The process according to  claim 12 , wherein separation in step c) is performed by a method selected from the group consisting of centrifugation, microfiltration, and combinations of any of the foregoing.  
     
     
         16 . The process according to  claim 12 , wherein the process steps a), b) and c) are run in continuous mode.  
     
     
         17 . The process according to  claim 12 , wherein said soluble portion of the fermentation broth produced in step c) is subjected to a method selected from the group consisting of column chromatography; crystallization; precipitation; ultrafiltration; or combinations of any of the foregoing.  
     
     
         18 . The process according to  claim 12 , wherein the cut-off value of the UF membrane is lower than about four times the molecular weight of the fermentation-derived product.  
     
     
         19 . The process according to  claim 12 , wherein said fermentation-derived product or a precursor thereof is a protein.  
     
     
         20 . The process according to  claim 19 , wherein said protein is selected from the group consisting of GLP-1, exendin-4, exendin-3, GLP-2, glucagon, TFF peptides, interleukins, insulin, albumin, precursors of any of the foregoing, and analogs of any of the foregoing.  
     
     
         21 . The process according to  claim 20 , wherein said protein is selected from the group consisting of human insulin, a human insulin precursor, a human insulin analog, a human insulin analog precursor, Arg 34 -GLP-1 (7-37), and GluGluAlaGluLys-Arg 34 -GLP-1(7-37).